You might have heard people saying "my sight is increased or decreased". What does it mean ?

You might have seen an electrician while using the screwdriver. What materials does it contain?

You might have noticed the marking of 500 W on an electrical appliance . What does it indicate ?

You might have seen an electrician while using the screwdriver. Why does a screwdriver used by electricians not have metal handle?

If each observation is increased or decreased by a; then the mean is also increased by a.

The poet says “No” in the beginning of the third stanza. What does he mean by this?

What is the trend in the atomic size in a group, does it increase or decrease?